The effects of environmental noise on children’s cognitive performance and annoyance

Abstract

In order to explore how noise affected children’s cognitive processes, laboratory experiments on children’s attention, short-term memory, calculation and reading work were carried out with noise stimuli of road traffic noise, low-frequency noise and white noise. Noise levels of the noise stimuli ranged from 35 dB(A) to 65 dB(A) to simulate indoor acoustic conditions, and the duration of noise stimuli in each experiment was determined by the length of cognitive task. A total of 248 children aged 7–12 years were recruited in these four experiments. In each experiment, participants were asked to finish certain cognitive tasks in different noise conditions and to evaluate annoyance brought by the noise stimuli. It was concluded that: 1) Regardless of the noise type, noise level directly affected subjective annoyance rather than cognitive performance. Annoyance increased linearly with the increase of noise levels. Compared with cognitive performance, subjective annoyance was more appropriate to measure the impact of noise levels on children. 2) Cognitive performance did not depend on noise level, but more on noise type, especially for younger children aged 7–10 years. 3) Noise type and non-acoustic factors, such as age and gender, had significant interaction effects on subjective annoyance and cognitive performance. In the complicated cognitive processes, the older the age, the greater the influence of noise type on subjective annoyance. For cognitive performance, the younger the child, the more affected by the noise type, and low-frequency noise was generally easy to cause worse cognitive performance. Boys were more susceptible to noise type than girls, and they showed higher noise annoyance than girls. And 4) the performance of complicated cognitive tasks was more influenced by noise than that of simple ones.